This invention relates to an apparatus and method for extracting biodegradable constituents from a fluid stream by the action of a cell culture, e.g., biomass which digests or assimilates such constituents. In particular, this invention relates to a biomass-based apparatus and method which incorporates a component to monitor and optimize the bioactivity of the system.
Often, it is desirable to remove biodegradable constituents, such as organic constituents and/or gaseous inorganic sulfur-containing or nitrogen-containing constituents, from a fluid stream. In particular, it is often desirable to remove such constituents from fluid process streams prior to their discharge or release.
Thermal oxidizers, incorporated into a vent stack, serve to oxidize organic components of a process stream principally to carbon dioxide and water. Such units require an input of energy, typically in the form of heat, to effect such oxidations. Such an input of energy greatly increases the operating costs of the system.
In contrast, biological systems are passive, i.e., they do not require an input of energy. Upon the passage of a stream containing a biodegradable constituent over a suitable biomass, the biomass consumes and/or degrades the constituent, producing a treated effluent stream. As the biomass is a living system, the maintenance of such factors as pH, temperature, oxygen concentration, carbon dioxide concentration, and nutrient concentration is essential if the biomass is to be sustained. Simple electrodes, probes, and sensors can provide basic information as to the condition of the process stream. Existing systems use the data collected from such instruments to estimate the bioactivity of the system, and the percent purification of the stream. Such estimations are generally made on the basis of samples taken from the process stream to a laboratory for analysis. Such analyses typically take at least thirty minutes per sample to complete. None of the systems known in the art make a real time, i.e., an on-line, measurement of the consumption of biodegradable constituents by the biomass. Such a real time measurement would be particularly advantageous in the control of biological systems to avoid system upsets. Results obtained at times much later than the time of sampling may be too late to prevent deleterious effects on the biomass.
Waste fluid streams often contain more than one constituent to be removed. Such streams also typically contain particulate matter. No known system permits the on-line determination of the amount of a biodegradable constituent removed from a dirty, complex process stream.
Prior activities in the relevant art have focused on the analysis of effluent gas or liquid streams, following the treatment thereof in a reactor. The concept of the on-line analysis of both the influent and effluent streams has not previously been reported. For complete and accurate characterization of a process, it would be preferable to analyze all streams, both influent and effluent, to avoid or minimize errors made from assumptions about the content of the influent streams. This is particularly true in waste water treatment applications, where the influent stream may represent a combination of the discharge streams from a multitude of manufacturing operations.
A biological system for the treatment of fluid streams which utilizes a means for directly measuring the consumption of biodegradable constituents by the biomass would hold significant advantages for industry. The envisioned system would permit the facile analysis of dirty, complex process streams. Further advantages would be realized in a system which utilizes an on-line means for monitoring the concentration and identity of constituents within the aqueous bath for the biomass. Such a system would enhance the detection of anomalies and dead spots within the system, and would improve the monitoring of the health of the biomass. Such a system would further enable the realization of a steady state or equilibrium, which translates to decreased, if not negligible, productions of biosludge.